The present invention relates to a method for intuitively checking the abnormality of an object.
Ultrasound systems transmit ultrasound signals from a surface of a human body or an animal body towards a predetermined part within the body (i.e., an object such as a fetus or internal organ) and use information about ultrasound signals reflected from a tissue within the body to obtain images related to a cross-section of a soft tissue or blood flow. Due to its compact and cheap design, real-time display, and high stability with no risk of exposure to X-rays or other radiations, such an ultrasound system has been widely used together with other image diagnostic devices such as an X-ray diagnostic device, a Computerized Tomography (CT) scanner, a Magnetic Resonance Image (MRI) device, and a nuclear medicine diagnostic device,
A common method for detecting a fetus with Down syndrome is to measure the thickness of a nuchal translucency (NT) in the fetus using an ultrasound system. According to this method that was devised by Nicolaides in 1992, if it is determined that a fetus has any abnormality, an NT thickness has increased due to subcutaneous accumulation of fluid at the back of a fetal neck.
In particular, a fetus with Down syndrome or other chromosomal abnormalities, or heart defects may usually have an increased NT. Thus, when a doctor measures the thickness of a translucent space behind a fetal neck using an ultrasound system and finds that the thickness of the translucent space exceeds 2.5 mm, a more accurate test, such as chorionic villus sampling or amniocentesis, is performed to see whether a fetus has an abnormality.
However, this approach has a problem that it is difficult to accurately measure the thickness of an NT because it may vary depending on an angle or measurement method. Thus, a doctor is inconvenienced in having to check whether an actual NT thickness is greater than 2.5 mm for each test before making conclusions about the abnormality of a fetus.